فصلنامه تحقیقات جنگل و صنوبر ایران
سال بیست و ششم شماره 4 (پیاپی 74، زمستان 1397)

According to the importance of hornbeam (Carpinus betulus L.) in Hyrcanian forests, studying cambium activity and tree-ring growth of this species with respect to different tree diameter classes can present information about the growth of these trees. Therefore, the beginning, the end, and the duration of cambium activity (growth period) as well as growth rate were studied in three different breath height diameter classes i.e. 25-35, 36-50 and 60-90 cm in 2016 growing season in Kheiroud forest. The study method was consecutive extracting of 1080 micro-cores from trees and further microscopic investigations. Results showed that the cambium activity of trees belonging to the first and second diameter classes started in late April and, respectively, continued until early and mid-October. In the third diameter class, cambium activity began with a significant delay compared to the first and second ones (late May) and ended earlier (late September). In addition, this class had the shortest duration of growth among classes resulting in much narrower tree rings. Younger trees (class one) showed a higher synchronization in the terms of daily growth rate while with increasing age and reaching the longevity, homogeneity in growth decreased. Overall, it seems that trees in the first and second diameter class were in the phase of maturity and thus the timing of their growth were similar, but old trees of the third diameter class, reaching the longevity of hornbeam, were very different from two other ones.

According to the positive role and symbiosis of ectomycorrhizal fungi for absorbing water and nutrition and transferring to trees, identification of them are of great importance. The aim of this study was to investigate the relationship between recognized ectomycorrhizal fungi and some soil chemical properties in the Flourd series of Farim forests, Mazandaran province. Forty five beech trees were measured in three elevation classes (1200-1500, 1500-1800, and 1800-2100m a.s.l.) and samples were taken from the root tips at a depth of 10 cm. ITS nrDNA was replicated and sequenced using ITS1F and ITS4B or ITS4 primer pairs, then was corrected by BioEdit software and studied in NCBI. After specified the desired tree for sampling root tips, a sample was taken next to the same tree at a depth of 10 cm to examine of soil chemical properties. The results of this study showed that 10 different families were identified that the most symbiosis was in the Russulaceae and Cortinariaceae families. The results showed that edaphic factors such as soil pH, N, P, K, and C in the first elevation were higher than two other elevations. Moreover, the results of statistical analysis showed that P, K, and pH had a significant difference. Our results suggested that forest site conditions and tree diversity can influence on soil properties and the richness of ectomycorrhizal fungi and consequently on forest ecosystem dynamic.

In order to identify the most productive and adaptable clones to local climate and introduce them to people for mass wood production, ten clones of Populus nigra L. were selected and were planted in Khorram Abad Agricultural Garden Station for five years (2010-2014). Variance analysis showed that the year and cologne factors had a significant impact on height, diameter, and volume increment. The result of mean comparisons showed that the highest (2.05 m) and lowest (0.14 m) of height increment were dedicated to P. nigra 63/135 clone in the fourth year and P. nigra 56/48 clone in the second year, respectively. Also the P. nigra 63/135 clone had the maximum diameter increment (2.57 cm) in the fifth year (2014) and P. nigra 56/48 clone had the minimum diameter increment in the second year. The P. nigra 63/135 and P. nigra 62/154 clones had the highest (7.18 cm) and lowest (0.4 cm) of volume increment in the fifth year, respectively. The qualitative study of different P. nigra clones showed that except for the P. nigra 56/72 and P. nigra 49/23clones which had low and moderate curved trunks, respectively, the other clones had smooth and straight trunks.

Smoke tree (Cotinus coggygria Scop.) is an attractive ornamental species that has medicinal properties. In this study, the effects of different levels of salt on plant growth and cow manure and vermicompost on increasing the salt tolerance of plant were investigated. In a factorial experiment and completely randomized design (CRD), three levels of organic amendments (1- soil, 2- 80% v/v soil + 20% v/v vermicompost, 3- 80% v/v soil + 20% v/v cow manure) and three levels of salinity (1, 4 and 7 dS.m-1) with three replications per treatments were applied. In this experiment, media without organic amendment was considered as control. Results showed that increasing soil salinity levels progressively decreased the growth characteristics and fresh and dry weight of plant. The highest height and diameter were observed in control plants and in 1 dS.m-1 salinity. Vermicompost treatment better than control and cow manure increased fresh and dry weight of shoot. The highest fresh and dry weight of shoots by 230.8 and 123.36 g respectively, were obtained in the highest salinity level (7 dS.m-1) and vermicompost treatment. In moderate and high levels of salt stress (4 and 7 dS.m-1) vermicompost better than cow manure could increase leaf area. Cow manure and vermicompost could reduce sodium and chloride of leaf to control and increase its potassium. Generally, the use of cow manure and vermicompost could improve the growth characteristics and nutrient absorption of plant under salt condition compare to the control.

Wildfire leads to accumulation of ash in the surface soil, which it can have effect on the biochemical cycle of elements in the ecosystem. The goal of this study was to investigate some ash chemical properties of wildfire in litter of the Brant`s oak (Quercus brantii Lindl.) and vegetation of forest floor and determination gradiant from beneath of tree crown to the outside of the tree crown. Ash samples were collected immediately after forest wildfire in the summer 2016 in the Darehvaran area in Marivan. One transect was installed on a couner line with 300 m long on burnt slope. Ten Brant`s oak trees were selected at 30 meters intervals. Three samples of ash were collected in each tree. The 3 positions of ash samples including: at a distance of 1.5 meters from the base trunk, tree crown border and five-meters far from tree crown. Chemical properties of ash samples were measured in laboratory. The results showed that the content of C, N and P of ash increased significantly with movement from tree trunk to outside. The content of Ca and Mg of ash decreased signifcanly by moving from tree trunks toward the spaces between them, but the amount of K increased signifcantly. The EC and the pH of the ash decreased from the trunk side to the outside of the tree crown. In general, it seems that intensity of the wildfire decreased by moving from the tree trunk to the space between the trees because of the difference in the amount of litter accumulated.

This study aimed to identify the silvicultural characteristics, geological structure, soil and climatic characteristics, and to form a table for the ecological needs of the Tecomella undulata (Roxb.) Seem.. Six T. undulata habitats in southern Iran were selected following specification of their range of occurrence. The results indicated the distribution of T. undulata in warm and southern Iran, from the coast of Persian Gulf at a height of 10 meters a.s.l in Moqdan (Bushehr) to 1612 meters a.s.l in Esfandaghe (Jiroft). Annual rainfall of the study area is 100 to 200 mm with an average annual temperature of 5 to 50 °C. The habitats had mostly light to moderate and more sandy to loamy sandy soil texture with low water storage capacity. The soil was rich in potassium, yet very poor in nitrogen and organic matter, the average acidity of saturated sand was 7 to 8 and its conductivity was 0.5 mm/m, which predominantly lie on sediments of the Quaternary and Tertiary periods. The average density of T. undulata per ha in the six habitats was 75. In addition, results showed the maximum height of 10.2 m and the mean diameter of 47.35 cm. The mean canopy area was 13.2 m2 (ranging between 1 and 20.5 m2). The flowering stage of T. undulata species usually starts in late march to the middle of May. Furthermore, seed ripening occurs in late June and early May in the habitats associated with the best acorn production (Dasht-e kooch- Jiroft).  Natural propagation of T. undulata is carried out through the seeds and roots sprouts. The results of this study provided useful information about autecology of T. undulata.

Renewal of wood volume by 3P method has been suggested to replace the 100% renewal method to reduce field work and costs. In this method and following selection of sample trees from marked trees, the volume of industrial trunks and firewood in trees are field-measured. In order to evaluate and compare the full and 3P renewal methods in the Parchiva forestry plan in Mazandaran province, 1184 maple, ironwood, alder, beech and hornbeam were selected. The trees were first measured by 100% renewal method, followed by separate allocation of actual volume to industrial, cordwood and total volumes according to the procedure of 3P method. Estimation of tree volume was done by 3P method in 10 replications. The results of paired samples t-test showed a significant difference between 100% and 3P renewal methods for maple, ironwood and alder, while no significant difference was observed for beech and hornbeam (p < 0.05). An independent samples t-test also showed that volume estimation by 3P method did not reveal any significant difference on maximum and minimum error levels. The results of this study suggested the 3P method as a cost- and time-effective alternative to the full renewal method.

Study of plant communities and analysis of the relationship between plants and environmental factors has always been considered as a fundamental issue in ecological studies. The vegetation of Dalab Park in the protected area of Manesht and Qalarang in Ilam province was studied using the Braun-Blanquet method. The study of the plant communities was carried out based on 44 phytosociological relevés. Data collection was analyzed by Factorielle Correspondence Analysis (FCA) and Cluster Analysis (CA) methods. In general, there were five different plant associations, including: Teucrio polii-Quercetum brantii, Aceri monspesulani-Quercetum brantii, Quercetum brantii, Acantholimono blakelochkii-Astragaletum veri and Celtido tournefortii-Aceretum monspesulani. These plant associations belong to Quercetea persica class and Quercetalia persica order. Analysis of environmental variables in vegetation communities showed that soil factors (clay%, sand%, T.N.V%, phosphorus, potassium and pH), topographic factors (altitude and percentage of slope), as well as the percentage of cover in the overstory of the forest were explained most variation in plant communities in this area.

The bux moth, Cydalima perspectalis Walker (Lep.: Crambidae), has been identified as the most important pest of the genus Buxus in the world. This pest was introduced into Iran in 2016 and became highly invasive and destructive on Buxus hyrcana Pojark in the Northern Forests of Iran. The aim of this study was the evaluation of botanical pesticide Azadirachtin (Neem Azal®) to control of the bux moth and its combination with Henna as a synergist. Experiments were performed in a completely randomized design and were evaluated on second instar larvae of C. perspectalis under laboratory conditions (27±1°C, 65±10 R.H. and 16:8 L:D). At first, the mortality rate of the three concentrations of the Azadirachtin (1500, 1000 and 250 ppm) with control (water) was analyzed in six replications, then the effect of combination of three concentrations of Neem Azal® + Henna powder were investigated with three replications. The mortality was recorded after 24, 48 and 72 h. Our findings indicated that the application of Neem Azal® + Henna powder as an inexpensive and available adjuvant compound in spray tank could reduce the recommended concentration up to 50% and become more affordable to control C. perspectalis. This synergistic effect was similar when the dose of insecticide becomes doubles.

According to the importance of Zagros forests and their sustainability, it is necessary to introduce sustainability management indicators being appropriate to these forests. For this purpose, forests of Firoozabad district belonging to Kermanshah were selected. The study area was screened and analyzed by DPSIR method to obtain a complete understanding of the relationship between phenomena and subjects. Then, based on the TOP Down method, the series of criteria and markers in different regions of the world were investigated. Indicator Reporting on the Integration of Environmental Concerns into Agricultural Policy (IRENA) was used to design the criteria and markers for sustainable management of Zagros forests. The initial list of markers and criteria was prepared by local stakeholders (A total of 30 people) using Likert scale. After calculating the mean and relative weight of scores, the final list of criteria and markers was prepared. The results of DPSIR process showed that the most important driving forces in the studied area were: poverty, inadequate job opportunities and loss of access to new knowledge and technologies. In our study, 5 criteria and 30 markers were introduced. Results showed the most important and the least important criteria in study area were legal and customary frameworks for forest management (with relative weight of 0.819) and extent and area percent of regional ecosystems (with relative weight of 0.65). The most important markers of the 5th criteria (the most important criteria) were the existence of solutions for eliminating disparities between farmers regarding grazing livestock, harvesting non-wood products and the rate of compliance with local customs in the exploitation of land and natural resources in the area.

In addition to industrially-compatible wood characteristics and resistance to pests and other threatening factors, plantation and development of the poplar saplings is important for production of wood products. Providing a suitable bed for feeding saplings is the next step that will be commonly achieved by fertilization in the nurseries. The purpose of this study was to determine the amount of chemical fertilizer needed for poplar nurseries, which was evaluated in complete (NPK) and incomplete (N) forms and by examining vegetative traits, as well as their resistance and sensitivity to biological disturbance agents at the end of the growth season. For this purpose, the study investigated 663 individuals of Populus deltoides 69/55 clone in randomized complete block design by five treatments in a nursery in Kiashahr, Guilan province. Statistical analysis showed that despite increasing sapling growth, fertilizer also increased the incidence of leaf spot disease. There was no disagreement on the prevalence of pests as a result of the use of fertilizers. Therefore, given the adverse consequences of the use of fertilizer, fertilizer in those nurseries is not recommended.

Assessing the changes in plant functional traits along the gradients is useful to understand their adaptation and response to the global and local environmental drivers. In order to determine the effect of elevation on morphological and physiological responses of oriental beech (Fagus orientalis Lipsky), samples of leaves were collected from southern and northern parts of trees crown at 700 m, 1200 m and 1700 m a.s.l in Masal forests of Guilan province. Analysis of variance showed a significant difference among the morphological and physiological characteristics between the populations (p < 0.05). The results also showed that the leaf area, specific leaf area and relative water content of the samples collected from the two parts of crowns increased with the increasing elevation and decreased from 1200m to 1700m. Furthermore, Chlorophyll a, chlorophyll b, total chlorophyll and carotenoid content in three different altitudes were higher in northern part of the crown of the trees. The results of the mean comparison of carotenoid contents showed that with increasing altitude (from low to high altitude), the amount of carotenoid in both parts of the crown increased. Moreover, the plasticity in northern and southern directions of the crowns suggested that highest plasticity on the northern direction was observed for carotenoids (0.6), whereas it was 0.84 in the southern half for the ratio of Chl a/Chl b. In terms of morphological properties, the highest average impact of the plasticity in the northern and southern parts of the crown were observed in the relative water content (respectively, 0.81 and 0.9). The average physiological plasticity increased among elevation gradients and showed higher values than morphological traits. Conclusively, the results of this study showed that beach populations respond to environmental changes by changing in leaf traits at different altitudes.